Design, structure, and application of conductive polymer hybrid materials: a comprehensive review of classification, fabrication, and multifunctionality

Abstract

Conductive polymer (CP) hybrids combine the electronic properties of polymers with the mechanical strength, thermal stability, and catalytic features of secondary materials. This review presents four major structural categories: core-shell assemblies, interpenetrating networks, layered composites, and dispersed nanocomposites. Each class is linked to fabrication routes such as in situ polymerization, electrochemical deposition, solution blending, and sol-gel techniques. We evaluated the influence of these structural forms on performance metrics, including electrical conductivity, flexibility, and long-term durability. Representative applications in sensing, energy storage, corrosion protection, and environmental remediation are examined to highlight their functional advantages and practical limitations. Challenges in synthesis, precision, material stability, and device integration are also discussed. A final roadmap connecting structural design choices to specific application outcomes and outlining priorities for the future development of scalable and multifunctional CP hybrid systems is presented.

Fig. 1. Structural classification and synthesis routes of CP hybrid materials. This schematic illustrates the four main classes of CP hybrid architectures: core–shell structures, interpenetrating polymer networks (IPNs), layered composites, and dispersed nanocomposites. For each category, commonly used components (e.g., carbon nanotubes, metal oxides, and silica particles) and fabrication strategies (in situ polymerization, electrochemical deposition, solution blending, and self-assembly) are discussed. The arrows represent the synthetic pathways connecting the polymer type, hybridization strategy, and resulting morphology. This classification aids in selecting tailored material designs for specific applications, such as supercapacitors, sensors, and corrosion-resistant coatings.

Fig. 2. Schematic illustration of the key synthesis routes for conducting polymer (CP) hybrid materials. This figure summarizes four major fabrication approaches for CP hybrid structures: in situ polymerization, ex situ blending, electrochemical deposition, and sol–gel processes. In situ polymerization enables the direct formation of CP on functionalized substrates, ensuring strong interfacial bonding and conformal coverage of the substrate. Ex situ blending allows the incorporation of preformed fillers into polymer matrices via solution casting or melt mixing. Electrochemical deposition enables precise control over the thickness and doping levels by voltage tuning. The sol–gel approach facilitates the integration of metal oxides and ceramics, offering porosity control and thermal stability. Each method is associated with distinct advantages and structural outcomes, allowing researchers to tailor CP hybrids for specific energy, sensing, and electronic applications.

Fig. 3. Structural taxonomy and synthesis-application interconnectivity of conductive polymer hybrid materials. The diagram maps key synthesis methods (e.g., in situ polymerization, electrochemical polymerization, and template-assisted methods) against representative structural configurations (e.g., core–shell, interpenetrated networks, and layered architectures) and links them to their dominant application domains, including energy storage, biomedical engineering, environmental remediation, and intelligent electronics. This multidimensional schematic underscores the influence of fabrication strategies on morphology and functional deployment across diverse fields.

Fig. 4. Structural taxonomy and synthesis-application interconnectivity of conductive polymer hybrid materials. This schematic visually maps the interlinked relationships among the synthesis strategies (e.g., in situ polymerization, electrochemical polymerization, and template-assisted self-assembly), structural forms (e.g., core–shell, layered, interpenetrated networks, and mixed architectures), and key application domains, including energy systems, environmental remediation, biomedical devices, and flexible electronics.

Fig. 5. Architecture-to-application mapping of CP hybrid materials in sensing technology. This flowchart links the key structural forms of CP hybrid materials, such as core–shell, IPNs, layered composites, and dispersed nanocomposites, with their respective advantages and dominant sensing applications. Core–shell hybrids offer enhanced electron mobility and are used in gas sensors and biosensors. IPNs provide structural flexibility, making them suitable for wearable and skin-based sensors. Layered structures enable anisotropic transport and are applied in humidity and pressure sensors. Dispersed composites offer scalable fabrication methods for disposable chemical sensors. This mapping provides a design framework for selecting appropriate CP architecture based on the sensor performance requirements and operating conditions.